Out-of-hospital, sudden cardiac arrests (SCA) claim the life of approximately 375,000 victims each year in the U.S. SCAs claim more lives than Alzheimer's, assault with firearms, breast cancer, colorectal cancer, HIV, diabetes, house fires, motor vehicle accidents, prostate cancer, suicides, and industrial accidents combined. Sudden cardiac arrest is most often caused by an abrupt deterioration of the heart's normal rhythm. This electrical rhythm, normal sinus rhythm, causes the heart to contract regularly and pump blood to the brain and throughout the body. In sudden cardiac arrest, the normal sinus rhythm abruptly deteriorates into a chaotic electrical rhythm, called ventricular fibrillation that fails to contract the heart. As a result, blood is not pumped out from the heart. The result is immediate unconsciousness and collapse, which, if untreated, progresses rapidly to death.
Since the 1970's, defibrillation has been the standard of care for cardiac arrests in medical settings, such as the hospital intensive care unit, the emergency room, or the ambulance. Defibrillation is the delivery of a therapeutic dose of electrical energy to the heart with a medical device called a defibrillator. In these medical settings, a manual defibrillator is used. The manual defibrillator requires a healthcare professional, usually a physician, to analyze the patient's heart rhythm on a cardiac monitor. When ventricular fibrillation is detected, the healthcare professional administers a shock to the heart with the defibrillator. The defibrillator's shock quiets the heart's chaotic rhythm and allows the heart's normal rhythm to take over. In this way, the defibrillator converts the heart's abnormal rhythm, ventricular fibrillation, back into the heart's normal rhythm, However, the majority of SCAs do not occur in medical settings where healthcare professionals and proper equipment are readily available. Unfortunately, the majority of sudden cardiac arrests occur in the community where people, live, work, and play. The cardiac arrest victim is usually located far away from healthcare professionals, and the life-saving medical equipment.
Prior to the late 1980's, nearly all patients who suffered a cardiac arrest out of the hospital died. The addition of the defibrillator for use by paramedics on ambulances improved survival, but the time required for paramedics to arrive to the scene of a cardiac emergency was still too long. Multiple research studies performed on out of hospital cardiac arrest, determined that “time to defibrillation” is the most significant determinant of whether the individual can survive the cardiac arrest. Studies have concluded that a defibrillatory shock must be applied to the heart within four minutes of collapse. Yet, most EMS response times are far in excess of four minutes. EMS response times are typically between 8 to 12 minutes.
To improve survival, the medical community embraced a new technology, the automated external defibrillator (AED), in the late 1980's. The AED is a computerized device that includes a software algorithm that was developed to read the victim's cardiac rhythm, and then advise the rescuer whether to press the shock button to apply a defibrillatory shock. In contrast to AEDs, manual defibrillators require that the healthcare provider using the medical device be familiar with cardiac rhythms, and be able to read the cardiac rhythm on a cardiac monitor which is attached to the patient's chest. The medical professional then determines whether or not a shock is indicated. The manual defibrillator plays the roll of delivering the shock, but does not diagnose the rhythm, nor determine whether a shock is indicated.
However, an AED assumes both that the individual using the device does not know how to read cardiac rhythms, and that the user would not be able to determine whether or not a shock is indicated. The AED itself includes an algorithm that analyzes the heart rhythm and determines whether or not a shock would be beneficial. Because the AED does not require any medical knowledge other than how to turn on the AED and follow the voice prompts, it can be used by non-healthcare providers, and can be located in the community where people live, work, and play, i.e. the locations where the majority of out-of-hospital sudden cardiac arrests occur. AEDs have been successfully used in the community by non-healthcare providers since 1988 in the U.S.
AEDs have been conclusively determined to read cardiac rhythms accurately, and properly advise whether a shock should be delivered. Their use by non-healthcare professionals has been proven to be safe. AED presence and use has expanded from the ambulance to the fire department to police departments, and in the last ten years to workplace settings, thus providing non-healthcare professionals, i.e. the lay public, the opportunity to provide the life-saving shock. Multiple reports in the medical literature have demonstrated that when an AED is applied prior to the arrival of emergency medical services (EMS), the chances of survival increase from approximately 8% to over 30%.
In 1993, the inventor recommended that organizations, such as corporate entities, should develop internal emergency response programs because of the time requirement to deliver a shock. These programs would include medical oversight, an emergency response plan, training and practice for members of the workforce to provide cardiopulmonary resuscitation (CPR) and operate an AED in their workplace, and proper maintenance of the AEDs installed at their facility. AED programs are implemented so that trained responders in an organization can provide CPR and the benefit of an AED to co-workers and visitors of the organization prior to the arrival of EMS. An important part of the program was to develop a system that would ensure that the AEDs would work properly when these medical devices were needed.
In the early 2000's, organizations began adopting the strategy of providing an onsite emergency response that included trained responders and AEDs. Some of the earliest adopters of AED Programs included airlines, such as American Airlines and United Airlines. The Federal Aviation Administration (FAA) mandated AED programs for all airlines that land in the United States.
As of 2013, more than two million AEDs have been sold, over one million of these to private sector organizations.
AEDs are composed of four parts:
1) The defibrillator unit, a computerized device that is capable of reading the cardiac rhythm, and advising whether or not a shock is indicated;
2) Batteries to power the device and the capacitor that delivers the shock;
3) Pads, that are to be placed on the patient's chest to read the cardiac rhythm, and deliver the shock; and
4) Connectors that connect that pads on the patient's chest to the defibrillator.
Currently, six major original equipment manufacturers (OEMs) manufacture and distribute eleven models of AEDs in the US. The major OEMs in the U.S. are Philips, Physio-Control, ZOLL Medical, HeartSine, Defibtech, and Cardiac Science.
An essential element of an AED program is establishing a system for proper maintenance of the AED unit itself. For example, AED pads expire between 2% and four years from the date of production, depending on the manufacturer's make and model, and require replacement. Similarly, AEDs use several types of batteries, including lithium batteries, and standard AA batteries, which expire between four and seven years from the time they are placed into service, and must be replaced. In addition, approximately 10-15% of AEDs have manufacturing errors that can occur on an individual device basis, or a design flaw on a make and model basis. These manufacturing and design errors typically require that the machine be repaired or replaced all together. Therefore, regular surveillance is required to ensure that the AED is properly functioning when it is needed in an emergency, such as a sudden cardiac arrest.
AED units perform automated daily self checks. During their daily self check, an AED unit tests itself to ensure that all of its parts meet minimum operational specifications. When an AED does not meet these minimum requirements, depending on the manufacturer's make and model, it beeps, turns off its ready light, and/or changes its status from a “✓” to an “x” to indicate a problem exists. Manufacturer recommendations for regular AED maintenance vary, but most, at the minimum require that an AED must be visually inspected once a month by an individual given responsibility for maintaining the proper functioning of the AED, usually called an AED coordinator, to determine if the AED is properly functioning.
This inspection process requires that the AED coordinator visually inspects the AED to ensure that the ready light is still blinking and that it is the correct color, and to ensure that the AED is not beeping or otherwise emitting a sound that indicates a problem exists. The AED coordinator must also ensure that pads and batteries are not expired and are still present, and that the AED unit has not been otherwise damaged or misplaced.
AED Device Failures
The U.S. Food and Drug Administration (FDA) regulates medical devices in the United States and collects post-approval data on device malfunctions. Patients, healthcare facilities, healthcare providers, or device manufacturers can report adverse events. FDA adverse event reporting is required by law if the device failure involves a patient fatality. Although the reporting is mandatory, it is likely that many non-healthcare professionals are unaware of this reporting requirement. In 2011, medical researchers performed a review of AED device failures reported to the FDA. They published their results in the Annals of Emergency Medicine. They reported that between 1993 and 2008, 40,787 AED adverse events were reported to the FDA. A fatality occurred in 1,284 of these AED adverse events. Researchers sought to determine the cause of the AED failure in these fatal events.
For cases, in which the researchers reasonably believed that they could draw a conclusion as to cause, they attributed approximately 50% of AED failures to battery or power problems, and 45% of AED failures to pads/connectors. A significant majority of these AED problems could have been detected by a reliable AED maintenance program following the manufacturer's recommended guidelines. When an AED Program is implemented at a new facility, a workforce volunteer is recruited to become the AED coordinator for that facility. One of this individual's ongoing responsibilities is to perform the monthly maintenance inspection of the AEDs in their facility. The AED coordinator can be in charge of inspecting between one and 30 AEDs, depending on the size of the facility, and the resources invested in the organization's AED Program.
Failure of Current AED Maintenance Systems
A systematic and sustainable AED maintenance program with strict accountability is lacking in the marketplace. The majority of AED maintenance programs in the industry use as their sole mechanism, an automated email notification system that sends reminder emails to perform monthly maintenance to the facility's designated AED coordinator.
AED program management providers typically collect the contact information for the AED coordinator, including their email address, and store this information in a database. Once the AEDs have been placed into service, the AED coordinator is sent an email notification on a monthly basis to perform the required AED maintenance.
AED programs based on automated email notification systems have failed for many reasons, including:
1) Technical failures, where emails fail to be received by the intended responsible party;
2) Personnel failures, where the responsible party fails to perform maintenance;
3) Lack of accountability, where there is a failure of the program vendor and/or manager to follow-up on the lack of performance by the responsible party; and
4) Lack of accountability, where there are inadequate mechanisms to determine if physical inspection of the device was actually performed.
Technical Failures
A variety of common technical issues cause AED program notification systems to fail. Notification emails may not reach the intended recipient because of technical errors, such as inaccurate data acquisition or data entry, such as simple spelling errors, or data input errors. Notification emails also fail because the recipient's email server inadvertently blocks it, especially with common email carriers such as Hotmail, AOL, Yahoo, or Google. The recipient's email server may also misdirect the email to the Junk or Spam folder. Any of these technical errors result in lack of notification of the responsible party.
Personnel Failures
Approximately 25% of AED coordinators discontinue providing maintenance due to relocation to another facility, reassignment to other job responsibilities, illness, retirement, or leaving the company. Often, another AED coordinator is not designated because the organization does not realize that maintenance is no longer being performed. Reassignment of this responsibility often is overlooked because the AED coordinators are volunteers, and performing maintenance is not part of their official job description. Other AED coordinators simply believe they are too busy or are not motivated to complete their AED maintenance responsibilities. They often do not notify the organization that they are no longer willing to perform their AED maintenance responsibilities. The result is that any AED device for which the party is responsible is no longer properly monitored and maintained. This significantly increases the risk that when the AED is required for a sudden cardiac arrest, it does not function properly, and a life is not saved.
Lack of Accountability
Lack of Follow-Up when Timely Maintenance is not Performed
Email notification systems are automated database-driven systems that routinely lack back-up mechanisms, such as people, to contact AED coordinators who are not performing the required timely maintenance. Typically, an AED coordinator's failure to perform the required in-person maintenance occurs because:
1) The AED coordinator did not receive emails notifying him of the need to perform maintenance;
2) The AED coordinator is no longer working in the facility; and
3) The AED coordinator no longer wishes to perform the AED maintenance responsibilities.
The vast majority of AED program vendors who use automated email notification systems provide no personal follow up when maintenance is not properly completed.
Lack of Confirmation that Required Inspection was Actually Performed
Lack of accountability also exists because of inadequate mechanisms to confirm that the required timely maintenance was actually performed as reported. Email notification systems require only that the recipient responds to the email notification or enters a response into the AED management database indicating that a physical inspection has been performed. Because AED coordinators are volunteers, and the AED program is seldom part of the organization's core business, nor the AED coordinator's job description, and the AED coordinator may simply electronically respond to the automated notification email rather than perform the required physical inspection. Simply checking the required box electronically to confirm that the email has been received provides no assurance that the AED is properly maintained.
In the inventor's experience, based on 24 years of managing AED programs, when an organization's AED program is audited to determine:
1) If the organization knows the location of their AEDs;
2) The name of the AED coordinator responsible for each AED;
3) If proper maintenance has been performed resulting in a functioning AED; and
4) If pads and batteries are expired,
the result is that a minimum of 25-35% of AEDs are not in compliance. Of the non-compliant AEDs, 20% of the devices do not have an active AED coordinator assigned, or their location is not known. An additional 10-15% of the machines have an assigned AED coordinator who is unwilling to perform the physical inspection.
These findings and the lack of accountability for maintaining functioning AEDs are major contributors to the significant number of AED failures reported to the FDA.